The characteristics of vegetation on embankment slopes with mowing management of over 10 years were studied. No significant effect of mowing frequency was noted on species diversity or degree of vegetation succession. Higher coverage of vine species and more number of bird-dispersed species were observed on slopes with high coverage of upper-story trees. Especially bird-dispersed vine species tended to survive because birds alight on these upper-story trees allowing easy seed dispersal and vines can often withstand mowing. Therefore, improvements such as reducing the coverage of upper-story trees and mowing at higher cutting height are necessary to suppress vine species.

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The slope stability mechanism of the shot-vegetation-spray method using fly ash as stabilizer discharged from thermal power stations without seeding foundation such as wire net was studied. Based on the classified destruction mechanism, the soil property tests and the horizontal loading tests were performed. The slope slide phenomena were evaluated on the digitization. From triaxial compression tests (UU tests), the cohesion C=23 * 10^-3N/mm², the angle of shear resistance φ= 26.4 degrees in the age of material of one day and C=5.2 * 10^-3N/mm², φ= 19.2 degrees in the age of material of five days were obtained. From the tests, the friction resistance 2.27 ∼ 4.42 * 10^-4N/mm² in the age of material of 0 day and 3.50 ∼ 6.91 * 10^-7N/mm² in the age of material of 14 days were obtained. Using the property test results and the soil properties by the references, the slope stability was studied. The results of this study suggested that, the shot-vegetation-spray method using fly ash without seeding foundation can be applied to the slope of up to 1:0.6inclination, if the natural ground slope is stable.

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Direct shear tests on soil specimens including roots of Festuca arundinacea Schreb. and Festuca longifolia Thuill. were conducted based on the soil dressing seed spraying Engineering. Water contents in soil specimens were different with the difference of slope directions, and this had influences both on cohesion, c and on angle of shear resistance, φ. When the soil specimen included the roots of two exotic herbaceous plants, the c values only increased. In addition, the c value indicated a maximum at the flatland. The c values of F. arundinacea were larger than that of F. longifolia with good growing condition. Not only the increment Δc of c value with the roots in soil specimens but also the value divided c value by root length density were almost same with any slope direction in two plants.

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We conducted a survey on vegetation and a sampling of topsoils on the riverbed of growing sites of 5 species (Sicyos angulatus L., Ambrosia trifida L., Coreopsis lanceolate L., Rudbeckia laciniata L. and Eragrostis curvula (Schrad.) Nees) in nationwide six rivers. After that, we performed a germination experiment using the sampled topsoils. We also analyzed Veronica anagallis-aquatica L. that germinated in the experiment. As a result, germination was obserbed in the second year of the experiment, with five species except Rudbeckia laciniata L., suggesting the formation of persistent soil seed banks.

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Triadica sebifera has already invaded the Forest of Takaragaike Park and logging activities have started, but it is necessary to promote the control activities systematically. We investigated the distribution of T. sebifera in the forest and surrounding area. We suggested areas with high priority to control based on the density of individuals with high possibility of seed production. The distance from fruiting individuals maximizes the distribution probability of T. sebifera, and the tree gaps in the valley were considered suitable for invasion. Using scenario analysis, we identified trees that can be cut down to lower the distribution probability in the forest.

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The list of harmful species for ecosystem was primarily created through compiling plants specialists' knowledge. However, collection of species' information and discussion takes a long time. A simple, but still effective evaluation method, needs to be created to be able to take quick countermeasures against alien species. The authors made a prototype evaluation model for evaluating alien species' invasiveness based on species characteristics. This new model showed high positive correlation between Pheloung (1999) and John & Linda's (2002) models, when 50 species growing in Japan were applied. Also, among all 200 of The list of harmful species for ecosystem, 48 species, including 16 invasive alien special species were extracted as “extremely high invasiveness” by the new model. However, 13 species were determined to have “no invasiveness,” proving that the model needs further improvement.

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Timing in the appearance of bare-ground is an important filter on vegetation development, which should be important for re-create desirable vegetation. A 3-yr vegetation monitoring was carried out in bare-grounds occurred at three different periods (March, July and September). The timing affected subsequent vegetation development. Plots disturbed in July tended to be dominated by Imperata cylindrica, whereas plots disturbed in March and September were dominated by Solidago altissima. Species compositions of both dispersed seeds and subsequent seedlings should be different at each season, which would lead to the differences in the coverage of dominant species and the number of species.

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To discuss an adaptability of Dianthus superbus L. var. longicalycinus against the huge tsunami, we investigated the density in three types of soil disturbance intensity on the tsunami-stricken coastal forest by the Great East Japan Earthquake in 2011. Average density was 90 to 96 individuals /m² in the topsoil outflow type in 2015 and 2016 respectively, and this type indicated significant high density for other type. There were a lot of bloomed individuals and seedlings in this topsoil outflow type. We thought that not only this wildflower has the tolerance to the disturbance, but this species made opportunity to increase in population.

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In a coastal pine forest in Tokushima prefecture, we created a canopy height model from Unmanned Aerial Vehicle (UAV) data using Structure from Motion (SfM), and estimated an index representing forest floor light condition for sustainable pine forest management. The canopy openness was estimated with high accuracies. Large size gaps were extracted in the most plots which have canopy openness larger than 30 %, and it implied that it is possible to extract areas having light conditions suitable for the growth of pine trees.

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Micro topographic change, wind conditions (wind velocity,wind direction) and the accumulation of shifting sands etc. were surveyed to verify the effect of the change of topographic and wind conditions by constructing sand fence on shifting sand damage in 2008 and 2014 at Shonan beach, Kanagawa Pref., Japan. As a result, It was considered that the factors of shifting sand damage were (a) existance of artifitial wind or sand barrier, (b) change of wind reduction range by the position of wind barrier. It was also cleared that the manner of accumulated amount of sand was different in each conditions (a) and (b) . Those results showed important suggestions for maintenance and management of coastal forest behind beach.

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To understand the establishment of an artificial urban forest the distribution of native herbaceous and woody plants in coniferous, broad-leaved and mixed stand types was studied. In coniferous stands and a coniferous area of mixed stands there were low-light conditions year-round and no specific species, such as Sasa nipponica, was dominant, but native herbaceous and woody plants were found to grow better. Brighter light conditions in the spring in broad-leaved stands and the broad-leaved area of mixed stands led to S. nipponica dominating and several native herbaceous species growing better as well, possibly suppressing the growth of woody plants.

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To clarify environmental conditions suitable for the flowering of Callicarpa japonica, we examined several factors. As a result, the sizes of C. japonica, the sum of the ratio of basal area of C. japonica to its competitors, and the slope angle of the habitat of C. japonica influenced the flowering. In the top two fitted generalized linear models, the sum of the ratio of basal area of C. japonica to its evergreen competitors within the radius of 4 m was selected as an explanatory variable. This suggests that the density of evergreen competitors within the radius of 4 m has influenced on the flowering of C. japonica.

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A mass flowering of Sasa veitchii var. hirsuta occurred in the 2000s in northern part of Kyoto City, and there was a possibility of hindrance to the regeneration caused by deer herbivory. In this research, we conducted a follow-up survey of the recovery process of Sasa community that bloomed in 2007. The impact of deer herbivory to the regeneration was examined through experimental removal of herbivory. As a result, decline of the community was clarified. Removal of herbivory is thought to promote regeneration since it was proved to be a significant inhibitory factor in the natural environment.

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This study investigated the seedlings establishment tendency and the factors affecting them (ex. deer-proof fencing, plot location) in forests damaged by oak-wilt disease and deer browsing in order to understand the restoration possibility. The deer-proof fence contributed to increase the seedling numbers. The species structure was related to the location and the sky factor. Plots located at the lower side of the slope with high sky factor showed some possibility of Q. serrata regeneration. However, plots located at the middle slope with lower sky factor show little possibility and were thought to be covered by shrub species like Ilex pedunculosa

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This study examined the effects of office greening on workers in the actual work environment. The survey focused on business and job categories. Different trends were seen when combining business and job categories: evaluations of the job or the workplace as well as feelings or emotional states improved. Additionally, the workers' responses to office greening were different between categories. Factors that were considered included the business contents, the workers’ impressions of plants, and the kinds of stress related to the job.

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In this research, we focused on rivers flowing through residential areas as precious natural environments of urban areas and investigated the preference of local residents to river space in order to examine better way of river environment. In this survey, using a questionnaire, we analyzed descriptions about the space preferred by residents by text mining. The river's spatial structure was classified into three groups, "undeveloped, spaces with fireflies and private houses", "space with maintenance and hydrophilic facilities", "tourist spot with promenade and cherry blossoms", due to reasons preferred by residents. On the other hand, it was suggested that the evaluation could be lowered by factors of the surrounding space such as excessive planting, private bridges, middle and high-rise buildings, even if the favorable elements were arranged.

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We inferred that Japan provided a habitat for pine trees from the representative anthology of Japanese poetry written from the 8th to 15th century and threw light on the changes in the habitat occurring every century. People have acknowledged the value of the vegetation-covered landscape characterized by Japanese Black Pine trees on the beaches, because it is always referred to in poetry. In addition, the percentage of the vegetation-covered landscape characterized by Japanese Red Pine trees in the mountains increased rapidly after the 13th century. Association with wind sounds and the diversification of terms alluding to a mountainous habitat were regarded as the reasons.

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We aimed to highlight the current condition and the potential of 33 kabuyutan in Ciomas Village, Indonesia. The ethnobotanical approaches were used to identify plant species. Through the free listing method, about 332 plant species were reported and a third four of them existed in kabuyutan. The findings strengthened the potential of kabuyutan to be local biodiversity hotspots which would support the global conservation strategy. However, more than half of species were exotic. We suggested that dissemination of knowledge is essential to nourish people's awareness in dealing with locality and environmental conservation by encouraging and strengthening the custodian's role.

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The weighing root-ball method to calibrate sap flow measurements was developed. This method detects the amount of transpiration as the changes in the weight of tree body and compared with heat ratio method applied on Acer palmatum Thunb. for two years. There is a high correlation between transpiration rate and the heat pulse velocity by HR method. In low velocity, linear regression was obtained, while in high velocity, a quadratic regression was obtained. Estimated sap flow rate increased in two years. The weighing root-ball method is suitable for calibration of sap flow techniques, in cases that nondestructive procedures are required.

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Evapotranspiration of Sedum is influenced by CAM induction, which is different between plant species. We measured the index of CAM induction and evapotranspiration in Sedum album, Sedum kamtschaticum, Sedum reflexum by non-destructive measurement to elucidate the relevance between physiological characteristics and changes in thermal environment. Evapotranspiration for a long period has decreased with CAM induction. Evapotranspiration for a short period has increased with the increasing of leaves weight ratio and we suggest that this may lead to the increasing of water retention. We concluded that gross evapotranspiration are dependent on both the index of CAM induction and leaves weight ratio.

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This paper presents the method for estimating coupled photosynthetic and stomatal conductance model parameters using Markov chain Monte Carlo (MCMC) method based on Metropolis algorithm. Photosynthesis model have important parameters to estimate photosynthetic rate. The parameter values vary a great deal depending on plant species and growth environment. For this reason appropriate parameter estimation is important to apply the model to understand biological process.

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Rice cropping produces a lot of waste material such as rice husks. New ways of the utilizing of rice husks are in urgent need. In this study, the ability of cement improved soil mixed with rice husk ash as greening material was evaluated by four kinds of examination: compression test, X-ray CT, permeability test, and water retention test. As a result, replacing 60 % of the cement with rice husk ash had a positive effect on pozzolanic reaction. And, the cement improved soil (replacement rate: 60 %) passed target values of porosity and permeability.

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In order to clarify the root distribution and the pull-out resistance of six Quercus serrata Murray grown at the slope with 5～48°angle, we measured the number and diameter of roots > 1 mm in diameter at horizontal and vertical plates of soil profiles (n=4,483) , and performed the pull-out tests (n=640) . The relationships between root diameter and pull-out resistance differed the roots < 30 mm from the all roots (ANCOVA, p<0.05) . The number of horizontal roots was larger than that of vertical roots (paired t-test, p<0.001 or p<0.05) . The roots at the gentle slope grew to downward than upward and the diameter was larger at with gentle slope than that at the steep slope (GLMM, p<0.05) .

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Tree-pulling experiments were conducted on sugi (Cryptomeria japonica and hinoki (Chamaecyparis obtusa) involving trees of various diameters, including large-diameter trees with >30 cm diameter at breast height (DBH), in central Mie prefecture. The critical turning moment of sugi and hinoki showed a high correlation with DBH. For belowground parameters, the critical turning moment of sugi showed a correlation with the depth of center point of rotation, and that of hinoki showed a correlation with depth of center point of rotation and root plate radius. Regression lines between critical turning moment and DBH of sugi differed from hinoki; the critical turning moment of hinoki was higher than that of same-sized sugi. The critical turning moment derived from regression lines between critical turning moment and DBH in this study were lower than that of previous studies.

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In this study, we attempted to clarify the deformation strength characteristics of fine-grained soil containing the root systems of herbaceous plants with a freeze-thaw history. Using Brassica rapa var. perviridis, we prepared specimens to simulate vegetation work, and conducted a direct shear test with specified unfrozen and freeze-thaw history. As a result, it was confirmed that the shear strength of fine-grained soil under low vertical stress increased for root systems in the unfrozen state. On the other hand, it was also revealed that states with a freeze-thaw history exhibited root system damage as well as decreased shear strength.

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Breaking seed dormancy during long-term cold storage before seeding is necessary because this could intensify dormancy because of the decreased moisture content. In this study, we investigated the effect of the temperature and duration of cold and the combination of warm and cold stratification on the germination of thirteen deciduous broad-leaved tree seeds. Seed dormancy was broken by cold stratification for about more than three months. The final percentage of germination of five species that were subjected to warm and cold stratification was less than 20.0 %. Euonymus sieboldianus and Viburnum dilatatum seeds, which did not germinate after cold stratification alone, were germinated after being subjected to a combination of warm and cold stratification; however, the final percentage of seed germination for the species subjected solely to cold stratification was low.

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The characteristics of seasonal change of dry matter allocation to component organs among juvenile (J), small size bolting (B1) and later stages individual of Lilium auratum Lindley were studied under the condition of cultivation. The threshold fresh weight of underground parts value of the transition from J to B1 stage was estimated approximately 0.666g. The B1 allocated higher proportion of dry matter for productive parts than J, which caused more 8 days required to recover weight in dormant period. The seasonal change of dry matter showed the presence of enough light environment from sprouting period to end of May in forest floor was required for maintaining Lilium auratum Lindley populations.

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Primula cuneifolia Ledeb. var. cuneifolia occurs in alpine regions of Hokkaido. It is described as rare species in the Red Data Book of Hokkaido because the individuals density is low anywhere. In this study, we attempted to determine the genetic variation of the species as useful information for conservation and restoration. Two natural populations of the species in Rausuko and Furanodake, were investigated to sequence two chloroplast DNA regions of trn L-trn F and atp B-rbc L. Consequently, some genetic variations were detected between the studied populations, not within the populations. This result suggests that the both populations are in a state sensitive to environmental changes.

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Changes in the adsorption patterns of the ¹³⁷Cs by litter was investigated in the test site of organic horizon removal in Yamakiya District of Kawamata Town, Fukushima Prefecture, using litterbag method and sequential extraction experiment. ¹³⁷Cs concentration of litterbag was increased from May to October. Unavailable form of ¹³⁷Cs increased from 17% in May to 76% at control site and 89% at organic horizon removal site in October. Immobilization of ¹³⁷Cs is considered to be caused by uptake by fungi and fixation by clay minerals, which was introduced into the litterbag by the work of the removal of organic horizon.

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For effective plant identification and tree management in the field, a prototype tablet terminal database system in Cerasus was developed. The database of 44 Cerasus species and cultivars was intended for Cerasus guide and management of planted treea on an urban campus. Target Cerasus species and cultivars could be extracted from the database with a single query key, such as name or flowering period or the combination of several keys. Tree images of current two years were automatically arranged in the database for tree management and the location of trees were revised with the WebGIS effectively.

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